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5. A rope is attached to a boat at water level, and a man on a dock is pulling on the rope at the rate of 30 ft/min. If the man's hands are 10 ft above the water level, a) how fast is the angle 0 changing as the boat approaches the dock when the length of the rope out is 12 ft. (Let 0 - angle that the rope makes with the horizontal) [7 pts] b) how fast is the boat approaching the dock when the length of rope out is 12 ft. [8 pts]